How to reset areas layout without losing data?
Save the project.
Go to the top menu and select: File&gt;New to open an empty file with the default layout.
Again on the File Menu, select &quot;File Open&quot;, when the window to select files appears press N  (or press the gear icon on the top right) to open the options tab.
Uncheck &quot;load UI&quot; and then select your file and open it.

The file should now open with the default user interface and layout.
I'm the future you can avoid creating a messy interface by using a layout instead of subdividing windows.